Amazing and very easy water trick
In this simple and amazing experiment, you can make it seem as though the arrows on a piece of paper move in the wrong direction. This is all due to refraction – as light passes through the glass, its speed changes and it refracts, slightly changing directions. The light eventually meets at a focal point outside of the glass and changes directions, resulting in a flipped image. This trick will come in handy when you will want to win a bet, impress someone, or even get the attention of the girl/boy you liked so much but she/he didn’t mind you.